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31.
Alison Burrells Julio Benavides German Cantón Jo?o L Garcia Paul M Bartley Mintu Nath Jackie Thomson Francesca Chianini Elisabeth A Innes Frank Katzer 《Veterinary research》2015,46(1)
As clinical toxoplasmosis is not considered a problem in pigs, the main reason to implement a control strategy against Toxoplasma gondii (T. gondii) in this species is to reduce the establishment of T. gondii tissue cysts in pork, consequently reducing the risk of the parasite entering the human food chain. Consumption of T. gondii tissue cysts from raw or undercooked meat is one of the main sources of human infection, with infected pork being considered a high risk. This study incorporates a mouse bioassay with molecular detection of T. gondii DNA to study the effectiveness of vaccination (incomplete S48 strain) in its ability to reduce tissue cyst burden in pigs, following oocyst (M4 strain) challenge. Results from the mouse bioassay show that 100% of mice which had received porcine tissues from vaccinated and challenged pigs survived compared with 51.1% of mice which received tissues from non-vaccinated and challenged pigs. The presence (or absence) of T. gondii DNA from individual mouse brains also confirmed these results. This indicates a reduction in viable T. gondii tissue cysts within tissues from pigs which have been previously vaccinated with the S48 strain. In addition, the study demonstrated that the main predilection sites for the parasite were found to be brain and highly vascular muscles (such as tongue, diaphragm, heart and masseter) of pigs, while meat cuts used as human food such as chop, loin, left tricep and left semitendinosus, had a lower burden of T. gondii tissue cysts. These promising results highlight the potential of S48 strain tachyzoites for reducing the number of T. gondii tissues cysts in pork and thus improving food safety. 相似文献
32.
Exotic slugs have become serious pests of canola, at establishment, in Southern Australian high-rainfall cropping zones. Slugs were monitored using relatively inexpensive 300 mm x 300 mm terracotta tiles acting as refuges. An investigation was made of the effects of the time of application of chelated iron baits on the slug species Deroceras reticulatum Müller and Lehmannia nyctelia Bourguignat. Baits reduced the number of surface-active slug species. A single application at sowing provided greater efficacy than one application before sowing, and efficacy was comparable with that of two applications. Canola seedling densities showed a negative response to D. reticulatum numbers; the presence of even one individual per refuge trap reduced seedling numbers below optimum densities. Thistles and other vegetation were associated with increased numbers of slugs. European guidelines for slug monitoring and damage appear to be at least partly applicable to Australian conditions. 相似文献
33.
Detection of Clinically Relevant Pain Relief in Cats with Degenerative Joint Disease Associated Pain
M.E. Gruen E. Griffith A. Thomson W. Simpson B.D.X. Lascelles 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):346-350
Background
Detection of clinically relevant pain relief in cats with degenerative joint disease (DJD) is complicated by a lack of validated outcome measures and a placebo effect.Hypothesis/Objectives
To evaluate a novel approach for detection of pain relief in cats with DJD.Animals
Fifty‐eight client‐owned cats.Methods
Prospective, double‐masked, placebo‐controlled, stratified, randomized, clinical study. Enrolled cats were 6–21 years of age, with owner‐observed mobility impairment, evidence of pain in at least 2 joints during orthopedic examination, and overlapping radiographic evidence of DJD, and underwent a 2‐week baseline period, 3‐week treatment period with placebo or meloxicam, and 3‐week masked washout period. Outcome measures were evaluated at days 0, 15, 36, and 57.Results
Both groups significantly improved after the treatment period (day 36) on client‐specific outcome measures (CSOM) and feline musculoskeletal pain index (FMPI) (P < .0001 for both); there was no difference between the groups on CSOM or FMPI score improvement. After the masked washout period, more cats that received meloxicam during the treatment period had a clinically relevant decrease in CSOM score (P = .048) and FMPI score (P = .021) than cats that received placebo.Conclusions and Clinical Importance
Using both a client‐specific and a general clinical metrology instrument, owners of cats with DJD were able to detect evident recurrence of clinical signs after withdrawal of active medication than after withdrawal of placebo, and that this study design might be a novel and useful way to circumvent the placebo effect and detect the efficacy of pain‐relieving medications. 相似文献34.
Ferdinando Nielsen Almeida John Kyaw Htoo John Thomson Hans Henrik Stein 《畜牧与生物技术杂志(英文版)》2014,(1):88-97
The primary objective of this experiment was to determine the effects of heat treatment on the standardized ileal digestibility(SID) of amino acids(AA) in corn distillers dried grains with solubles(DDGS) fed to growing pigs. The second objective was to develop regression equations that may be used to predict the concentration of SID AA in corn DDGS. A source of corn DDGS was divided into 4 batches that were either not autoclaved or autoclaved at130°C for 10, 20, or 30 min. Four diets containing DDGS from each of the 4 batches were formulated with DDGS being the only source of AA and CP in the diets. A N-free diet also was formulated and used to determine the basal endogenous losses of CP and AA. Ten growing pigs(initial BW: 53.5 ± 3.9 kg) were surgically equipped with a T-cannula in the distal ileum and allotted to a replicated 5 × 4 Youden square design with 5 diets and 4 periods in each square. The SID of CP decreased linearly(P 0.05) from 77.9% in non-autoclaved DDGS to 72.1, 66.1, and 68.5% in the DDGS samples that were autoclaved for 10, 20, or 30 min, respectively. The SID of lysine was quadratically reduced(P 0.05) from 66.8% in the non-autoclaved DDGS to 54.9, 55.3, and 51.9% in the DDGS autoclaved for 10, 20, or30 min, respectively. The concentrations of SID Arginine, Histidine, Leucine, Lysine, Methionine, Phenylalanine, or Threonine may be best predicted by equations that include the concentration of acid detergent insoluble N in the model(r2= 0.76, 0.68, 0.67, 0.84, 0.76, 0.73, or 0.54, respectively). The concentrations of SID Isoleucine and Valine were predicted(r2= 0.58 and 0.54, respectively) by the Lysine:CP ratio, whereas the concentration of SID Tryptophan was predicted(r2= 0.70) by the analyzed concentration of Tryptophan in DDGS. In conclusion, the SID of AA is decreased as a result of heat damage and the concentration of SID AA in heat-damaged DDGS may be predicted by regression equations developed in this experiment. 相似文献
35.
Excavating sponges that are destructive to farmed pearl oysters in Western and Northern Australia 总被引:1,自引:0,他引:1
Species of the family Clionaidae (Porifera: Demospongiae) that excavate shell of the silver‐lip pearl oyster, Pinctada maxima, in north Western and Northern Australia are described. Two species belong to the genus Cliona and one species to the closely related genus Pione. Cliona orientalis has only recently been reported from Australia in living and dead coral on the Great Barrier Reef, and this is the first report of this species from north Western and Northern Australia. Cliona dissimilis is reported from Australia for the first time. Pione velans was first described from Shark Bay, Western Australia and this study extends its distribution from Albany, south Western Australia to Port Bremer in the Northern Territory. The most common species found was C. dissimilis. Pione velans and C. orientalis were also present, although the latter species was rare. Cliona dissimilis and P. velans were found to be sexually reproductive in some shells with specimens of C. dissimilis with oocytes in May and P. velans in September 1999. Egg development was synchronous, indicating that the sponges were oviparous and would broadcast gametes in a spawning event. 相似文献
36.
37.
Taylor DL Thomson PC de Silva K Whittington RJ 《Veterinary immunology and immunopathology》2007,115(1-2):43-55
Reference genes are frequently used to normalize between different biological samples the levels of mRNA measured using quantitative PCR (qPCR). The expression level of many commonly used reference genes has been shown to vary between tissues or cells, or following exposure to various treatments including infection with microbes. The selection of an appropriate reference gene for an individual experiment is therefore a crucial step in the process of accurately determining changes in gene expression. For this purpose, we analyzed the expression of nine commonly used reference genes in a murine macrophage cell line, RAW264.7, for their potential use in the analysis of differential gene expression by quantitative polymerase chain reaction (qPCR) following experimental infection with Mycobacterium avium subsp. paratuberculosis. Only one of nine putative reference genes tested, casc3a, was found to be suitable, and combinations of two or more reference genes were disadvantageous. Based on data from the study, we recommend an approach for selection of reference genes, conducting assays with technical replicates in duplicate rather than triplicate, determining decision-limit quality control criteria for technical replicates and assessing the significance of gene expression fold differences using DeltaDeltaC(t) based on knowledge of the variation in the reference gene. 相似文献
38.
39.
Elizabeth A. Thomson Samuel N. Luoma Daniel J. Cain Christopher Johansson 《Water, air, and soil pollution》1980,14(1):215-233
Concentrations of extractable Cu, Zn, Fe and Mn in oxidized estuarine sediment are influenced by the manner and time of storage between collection and extraction. No storage method tested completely preserves the initial chemical and physical characteristics of the sediment. Freezing or (for some extractions) drying are adequate methods of storage if sediments are to be extracted only with acids. However, if a variety of extractants is to be used, extractions should be conducted as soon as practical after collection. 相似文献
40.
F.N. Green R. Baur Morellen Thomson Lesley McCarthy 《Genetic Resources and Crop Evolution》1997,44(6):491-493
Genetic lines and example cultivars are used as markers to define variation when describing or evaluating wild or cultivated germplasm. Occasionally genotypes previously described in the literature are no longer available. This was thought to be the case for chartreuse skin colour in Onion. However, registration authorities undertaking Distinctness, Uniformity and Stability tests recently observed this skin colour in the cultivar Greenella and have provided seed to a genebank for long-term conservation. This characteristic is suitable both for use as a genetic marker and as an example cultivar for describing Onion skin colours. 相似文献